There are four fundamental interactions/forces in nature. Gravitation, electromagnetism, strong-nuclear, and weak nuclear. All phenomena are due to the presence of one or more of these interactions. Forces act on objects and can act at a distance through a respective physical field causing a change in motion or in the state of matter.

In very small scales our world is subjected to the laws of quantum mechanics. All matter and radiation exhibit both wave and particle properties. We cannot simultaneously know the position and the momentum of a particle.

Earth is very small part of the universe. The universe is comprised of billions of galaxies, each of which contains billions of stars (suns) and other celestial objects. Earth is a very small part of a solar system with our sun in its center that in turn is a very small part of the universe.

Earth is a system of systems which influences and is influenced by life on the planet. The processes occuring within this system influence the evolution of our planet, shapes its climate and surface. The solar system also influences Earth and life on the planet.

All matter in the Universe is made of very small particles. They are in constant motion and the bonds between them are formed by interactions between them. Elementary particles as we know them so far from atoms and atoms form molecules. There is a finite number of types of atoms in the universe which are the elements of the periodic table.